Folding knife



FIG. 1 is a perspective view of a folding knife, showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines in the drawings depict portions of the folding knife that form no part of the claimed design. 

CLAIM We claim the ornamental design for a folding knife, as shown and described. 